Another very valuable comment in today's 2010 vs 2007 Uni Bremen Comparison blog post pointed me to a considerable partial disintegration of the ice bridge in McClure Strait. This is the last part of the direct route of the Northwest Passage, and, excepting the large amounts of ice floes in Melville Sound and Parry Channel (which are easily blown out towards the warmer waters of Baffin Bay, see image), the only thing that is preventing a very early opening of the Northwest Passage this year.
I had already been saving images this past week because of the reasonably clear skies over much of the Canadian Archipelago, and together with this latest image they show the break-off very nicely:
Notice also the breaking off of floes in McClintock Channel in the middle left of the image. I'll be updating this image the coming few days, so we can see what is happening to those ice floes and the rest of the ice bridge.
Update June 29th: Added yesterday's image (day 179). Some floes are breaking off at the bottom of the ice bridge. Check Nick Barnes' comments below for further observations.
Update June 30th: Added yesterday's image (day 180).
Update July 1st: Added yesterday's image (day 181).
Update July 2nd: Added yesterday's image (day 182). Nick Barnes has commented in the SIE update 10 thread:
Check out today's Terra image for the crack showing the next big loss at the eastern end of the ice bridge in the NWP: a big triangle of ice, with its base across the whole of Viscount Melville Sound (about 140km N/S, and maybe 60km E/W). The Aqua image shows that two more triangles are ready to come after that, after which there'll be about 150-200km of ice bridge remaining in the deepwater channel. The other side of Stefansson Island, there's another 30km chunk breaking off in the McClintock Channel.
The eastern end of the ice bridge in the picture is the lower end. Maybe I should rotate the image?
Update July 3rd: Added yesterday's image (day 183). Ice floes keep breaking off.
Update July 4th: Added yesterday's image (day 184). There's some serious cracking going on in the eastern side (lower side of the picture) of Melville Sound.
Update July 5th: I've made a new and improved animation. No more updates here.
The Cryosphere Today concentrations predicted this break-up nicely the last week. It looks like they have about 60-80% ice in the area right now so we should expect it to break up pretty quickly now.
Posted by: Andrew Borst | June 28, 2010 at 04:48
I have been looking at this area for the past few weeks. I was expectng breakup earlier, as it appeared that there was cracks in the eastern end also, but i now believe they are are cracks that refroze during the winter, and now may be long melt ponds.
I have been on vacation the past few days, and for another week, and I have just come in from the woods, to find that the pace of the decline accelerating, with two century melt days, and a close third.
It is really amazing to see the arctic change so quickly, especially when you are away from the computer for four days.
Posted by: Lord Soth | June 28, 2010 at 15:16
In today's photo, a 20km-wide strip has broken off at the eastern end of the ice (by Stefansson Island). Also breaking up: the ice in Dolphin and Union Strait - the southern route. Less important for navigation but still good to watch: Penny Strait, between Bathurst Island and Devon Island in the Queen Elizabeth Islands.
Posted by: Nick Barnes | June 29, 2010 at 00:23
According to climateprogress, NSDIC believes that the key to this year's melt is the Pacific side - the Beaufort and Chuckchi Seas. It will be interesting to see how the melting proceeds once Hudson Bay and the Canadian archipelego is ice-free. The next two weeks were the basis for the 2007 record. We just missed a century break yesterday, so 2010 is still close to the 2007 melt speed.
Posted by: Evilreductionist.blogspot.com | June 29, 2010 at 03:29
Just a quick post with another wild example of the warmth of the Canadian Arctic, where minima have regularly been well above climatic norms.
Sachs Harbor, in the NWT, is forecast to experience minima averaging close to 10 C for the coming week, and maxima close to 15 C. The norms are 3 and 10 C, respectively!
In some cases, the forecast minima are well above the normal maxima.
That's why I think Goddard is so out to lunch with his recent prediction of a downturn in melt rate within three days.
Posted by: Kevin McKinney | June 29, 2010 at 14:39